... [2,3], a rate-limitingenzyme in the synthesis of NAD+from nicotin-amide. Visfatin ⁄ PBEF ⁄ NAMPT is synthesized and secreted in adipose tissue by adipocytes, and mostly by macrophages, and circulates ... the absence or in the presence of the PPARc agonist GW1929 added at the start of the differentiation process [25]. As shown inFig. 4B, the expression of visfatin was significantlydecreased by ... of adipocytes,but also of several other types of cells, includingmacrophages, lymphocytes and endothelial cells. Ithas been shown that PPARc agonists induce the expression of visfatin in the...